DE102016222824B4 - Battery for a motor vehicle and motor vehicle - Google Patents

Abstract

The invention relates to a battery for a motor vehicle with at least one battery module (12), which has a plurality of battery cells which are arranged in a module housing (14) of the battery module (12), and with a carrying device (16) on which the at least a battery module (12) is fixed. The at least one battery module (12) is fixed by means of at least one screw (20) on the support means (16), which engages in a nut (32). A structural element (44) of the nut (32) and a structural element (46) of the module housing (14) form a positive connection with one another. Furthermore, the invention relates to a motor vehicle with such a battery.

Description

The invention relates to a battery for a motor vehicle, comprising at least one battery module having a plurality of battery cells. The battery cells are arranged in a module housing of the battery module. The at least one battery module is fixed to a support device. Furthermore, the invention relates to a motor vehicle with such a battery.

The US 2007/0087266 A1 describes a battery for an electric vehicle with a plurality of battery modules, which are fastened by means of rails in a system housing, wherein the rails are screwed by means of screws to the system housing on the one hand and with end plates of the respective modules. For this purpose, welding bolts are arranged in the region of ribs of the end plates, in which the screws are screwed.

The US 5,301,765 A describes the installation of a battery pack in an electric vehicle. The battery pack includes a plurality of electrically interconnected batteries disposed in a housing. On the housing electrical connectors are arranged. The electrical connectors are connected during assembly of the battery pack in the electric vehicle with corresponding, designed as receptacles or pins connections. The receptacles and pins are arranged on the vehicle side on a wall of a receiving compartment.

Batteries, in particular high-voltage batteries for motor vehicles, can be subdivided systemically into a high-voltage storage component and an electronic component. The high-voltage storage component in this case comprises the battery cells, which are in particular electrically conductively connected together in respective battery modules. The electronics part may include fuses, capacitors, controllers such as a battery management controller, a module management controller, a cell management controller, contactors, and the like. Much of the electronic components such as fuses, capacitors, contactors, circuit boards and the like are housed in a separate module, which is also referred to as battery junction boxes (BJB, battery junction box).

The high-voltage storage portion with the electrically conductive interconnected battery modules is housed in particular in a separate battery case. For fastening the battery modules to the battery housing, it can be provided that the respective battery module is fixed to it by means of four screw connections.

A disadvantage here is the fact that then the battery modules are attached only by a frictional connection to the housing. Accordingly, only the assembly preload force and only the friction occurring on a support surface of a screw head of the respective screw ensure that the battery modules can be moved as little as possible. In such a design, depending on the design profile, a high preload force is determined or set, and a robust screw connection must be defined. Accordingly, comparatively high demands are placed on the strength of the screws. This is associated with a relatively high cost.

Object of the present invention is therefore to provide a battery of the type mentioned, in which an improved attachment of at least one battery module is given, and to provide a motor vehicle with such a battery.

This object is achieved by a battery having the features of claim 1 and by a motor vehicle having the features of claim 10. Advantageous embodiments with expedient developments of the invention are specified in the dependent claims.

The battery according to the invention for a motor vehicle comprises at least one battery module. The battery module has a plurality of battery cells, which are arranged in a module housing of the battery module. The battery comprises a carrying device to which the at least one battery module is fixed. Here, the at least one battery module is fixed by means of a screw on the support device, which engages in a nut. A structural element of the nut and a structural element of the module housing form a positive connection with one another.

According to the invention, the nut is designed as a blind rivet nut, which has a projection as the structural element of the nut. The structural element of the module housing comprises a recess formed in the module housing and corresponding to the projection. The projection is received in the recess. Such a configuration of the structural elements makes it particularly possible to prevent displacement of the at least one battery module relative to the support device in the plane perpendicular to the longitudinal axis of the screw. Furthermore, during assembly, the at least one battery module can be positioned in a particularly accurate position and exactly relative to the carrying device before the at least one screw is tightened. In addition, it can be the rivet nut provide the projection particularly simple and little effort.

Due to the positive connection between the structural element of the nut and the structural element of the module housing, movement of the battery module relative to the support device in a plane oriented perpendicular to a longitudinal axis of the screw is particularly largely prevented. Accordingly, not only the screws need to ensure that the movement of the at least one battery module relative to the support device in this plane is limited as much as possible.

Therefore, the screwing can be adjusted. As a result, the assembly biasing force to be applied by the screw can be lower than when the at least one battery module is fixed to the support device without the formation of the positive connection between the nut and the module housing. Thus, for example, instead of a comparatively robust screw, a less robust screw can be used to fix the battery module to the carrying device. This has a significant economic advantage, especially when using a large number of screws per battery, as cost savings can be achieved.

Furthermore, improved mounting tolerances can be achieved when fixing the at least one battery module to the carrying device. In particular, when the battery has a plurality of battery modules, so can achieve a particularly compact design of the battery.

Furthermore, it is achieved that the at least one battery module in the mounting plane, ie in the plane perpendicular to the longitudinal axis of the screw, can no longer translate due to loads occurring during operation. As a result, mechanical influences on electrically conductive connections, for example, between individual battery modules, significantly reduced. The electrically conductive connections can thus be made particularly simple with regard to displacements and force influences to which they are exposed.

In particular, with regard to the advantages mentioned above, therefore, an improved attachment of the at least one battery module is given.

Preferably, the projection is formed as a cone with a central passage opening for the screw. In this case, a shaft of the screw passes through a fastening eye, which is formed on the module housing. By forming the projection provided on the side of the blind rivet nut as a cone and, correspondingly, the indentation in the module housing as a chamfer, self-centering of the battery module can already be achieved when the at least one battery module is placed on the region of the carrying device provided for the battery module. This facilitates the assembly and leads to a particularly high precision when setting the at least one battery module to the support device.

Preferably, the fastening eye has a determinable in the direction of the shank of the screw length, which is more than a quarter of a determinable in the direction of the shank of the screw height of the module housing. Then the fastening eye is designed to be particularly robust, and the attachment of the at least one battery module to the support device is particularly resilient.

Preferably, the blind rivet nut has a collar which adjoins the cone in the radial direction, the upper side of which rests against an underside of a fastening region of the module housing. By such a configuration of the blind rivet nut, a comparatively large-area contact of the module housing to the blind rivet nut is achieved even when providing the positive connection. This ensures good load distribution and is conducive to a particularly secure attachment of the at least one battery module to the support device.

The support means may comprise a bottom part and at least one side wall of a receiving compartment of a battery case of the battery. By means of the at least one side wall, in particular by a plurality of side walls, the receiving compartment for the battery module can be provided particularly well and simply in cooperation with the bottom part. In particular, when providing a plurality of battery modules in the battery, such receiving compartments or compartments serve to improve the mechanical behavior of the battery.

Preferably, a tab through which a free end of the nut passes, and which is spaced from the bottom part, is connected to the at least one side wall. This makes it possible to achieve a particularly robust fixing of the battery module to the carrying device. This is especially true if the tab is formed integrally with the at least one side wall.

As shown further advantageous, when the module housing is formed substantially cuboid and is fixed by means of at least two screws, in particular by means of four screws on the support means. Here, the screws are arranged in corner regions of the module housing. The mother assigned to a respective screw has in each case the structural element. By the distribution the, in particular four, screws on the corner regions of the module housing can be achieved with respect to the distribution of force particularly uniform fixing of the battery module to the support device. This ensures a beneficial longevity of the connection.

Due to the fact that the nut assigned to the respective screw has in each case the structural element, particularly many identical parts are used in the battery. This serves a particularly simple, cost-effective and process-reliable production of the battery.

In this case, it has proven to be advantageous if, in a first of the corner regions, the module housing comprises, as the structural element of the module housing, a depression formed in the module housing, whose internal dimensions correspond to external dimensions of the projection. The module housing has in a further, in particular the first corner region diagonally opposite corner region as the structural element of the module housing a formed in the module housing, slot-shaped depression. The slot-shaped depression extends in the direction of a connecting line from the first corner area to the further corner area. Thus, manufacturing tolerances and assembly tolerances can be well taken into account. Nevertheless, such a freedom of movement of the module housing, in particular a freedom from rotation about the first corner area, particularly largely limited.

The battery is preferably designed as a high-voltage battery, which has a plurality of the battery modules fixed to the carrying device. Such a high-voltage battery, which provides a rated voltage of more than 60 volts, for example a nominal voltage of about 300 volts to about 600 volts, can be used particularly well as an electrical energy storage for the motor vehicle, such as when the motor vehicle is designed as an electric vehicle or as a hybrid vehicle.

The motor vehicle according to the invention comprises at least one battery according to the invention. By means of the battery, electrical energy can preferably be provided for a drive unit of the motor vehicle designed to move the motor vehicle.

The advantages and preferred embodiments described for the battery according to the invention also apply to the motor vehicle according to the invention and vice versa.

• 1 ausschnittsweise eine Batterie eines Kraftfahrzeugs, bei welcher jeweilige Batteriemodule in jeweiligen Aufnahmefächern einer Trageinrichtung angeordnet sind;
• 2 in einer vergrößerten Detailansicht eine Blindnietmutter, welche zum Festlegen des jeweiligen Batteriemoduls an einer Seitenwand der Trageinrichtung ausgebildet ist; und
• 3 in einer schematischen Schnittansicht einen Ausschnitt des Batteriemoduls in einem Befestigungsbereich, in welchem das Batteriemodul an der Blindnietmutter anliegt.

In the following an embodiment of the invention is described. This shows:

• 1 a section of a battery of a motor vehicle, in which respective battery modules are arranged in respective receiving compartments of a carrying device;
• 2 in an enlarged detail view of a blind rivet nut, which is designed for fixing the respective battery module to a side wall of the support device; and
• 3 in a schematic sectional view of a section of the battery module in a mounting region in which the battery module rests against the blind rivet nut.

The exemplary embodiment explained below is a preferred embodiment of the invention. In the exemplary embodiment, the described components of the embodiment each represent individual features of the invention that are to be considered independently of one another, which also each independently further develop the invention and thus also individually or in a different combination than the one shown as part of the invention. Furthermore, the described embodiment can also be supplemented by further features of the invention already described.

In the figures, functionally identical elements are each provided with the same reference numerals.

In 1 are fragmentary components of a battery 10 a motor vehicle shown. The battery 10 includes a plurality of battery modules 12 , Each of the battery modules 12 includes a plurality of individual battery cells, which are electrically connected to each other. The battery cells (not shown) have respective battery cell housings with electrical terminals and are in a respective module housing 14 of the battery module 12 arranged. The battery cells can be in the respective battery module 12 be electrically parallel and / or in series. By a parallel connection of the battery cells can be from the battery module 12 provide a higher current than would be the case with a single battery cell. And by a series connection of the battery cells can be from the battery module 12 provide a higher voltage than can be provided by a single battery cell. Accordingly, by interconnecting the battery modules 12 a battery designed as a high-voltage battery 10 be provided as it can be used in an electric vehicle or hybrid vehicle for example.

The battery 10 further comprises a carrying device 16 which is part of a battery case. The carrying device 16 the battery case is in a plurality of storage compartments 18 or Divided sections, wherein in a respective receptacle 18 a respective battery module 12 placed and mounted. In 1 is one of the battery modules 12 outside of this battery module 12 associated receiving compartment 18 shown so that the components of the carrying device 16 in the area of the respective receiving compartment 18 are more recognizable. Dividing the battery case or battery system case into different compartments or storage compartments 18 in particular serves to improve the mechanical behavior of the battery 10 ,

For attaching the respective battery module 12 in the respective storage compartment 18 come preferably four screws 20 for use. In 3 is from such a screw 20 a shaft 22 shown schematically. In 1 are only the places where the battery module 12 by means of screws 20 on the carrying device 16 screwed or fastened, by respective arrows 24 illustrated.

Accordingly, the respective module housing 14 present cuboid, and the screws 20 are in respective corner areas 26 of the module housing 14 arranged. Here are the screws 20 through respective fastening eyes 28 passed, which in the corner areas 26 of the module housing 14 are formed. The sleeve-shaped attachment eyes 28 extend over about half of a height 30 of the module housing 14 , The height 30 measured here in the direction of the arrows 24 , which with the axis or longitudinal axis of the shaft 22 the screw 20 coincides. In 3 is the direction of the height 30 also indicated by the vertical direction z, which may coincide in particular with the direction of the vehicle vertical axis of the motor vehicle when the battery 10 is installed in the motor vehicle.

These are the individual battery modules 12 by means of an additional positive connection with the support device 16 connected to the battery case. This positive connection is in a particularly compact and space-neutral manner in the interaction of preferably as blind rivet nuts 32 formed nuts with structural elements of the module housing 14 provided. The blind rivet nuts 32 are in respective corners of the receiving compartment 18 arranged.

2 shows in an enlarged perspective view of such a corner of the receiving compartment 18 with one of the blind rivet nuts 32 , A free end 34 the blind rivet nut 32 comes through a tab 36 through which integrally with a, in particular made of metal, side wall 38 of the receiving compartment 18 the carrying device 16 is trained. Another side wall 40 limited to the storage compartment 18 frontally. From a bottom part 42 the carrying device 16 is the tab 36 spaced.

As a structural element for forming the positive connection with the module housing 14 has the blind rivet nut 32 a present designed as a cone projection 44 on. With this cone or projection 44 corresponds to one on the side of the module housing 14 provided structural element in the form of a depression 46 (see 3 ). The depression 46 is as a chamfer or a chamfered indentation in a fastening eye 28 comprehensive mounting area of the module housing 14 educated.

In the radial direction closes at the present designed as a cone projection 44 a collar 48 at. A top 50 of the collar 48 lies on a bottom 52 the mounting area of the module housing 14 on (compare 3 ). Because of the battery modules 12 with the wells 46 or chamfers are provided as a structural element and the blind rivet nut 32 with the lead 44 , is a displaceability of the battery modules 12 in a plane perpendicular to the shaft 22 the screw 20 (see 3 ) is particularly limited.

This brings with it that of the particular screw 20 applied mounting biasing force compared to the assembly in a use of blind rivet nuts without the projection 44 sinks. It can therefore use the less robust screw instead of a robust screw with an M6 ISO metric thread and a 10.9 grade of strength 20 with, for example, an ISO metric thread of the M6 specification and the strength class 8.8 be used. When in the battery 10 For example, a number of 36 battery modules 12 is used, this means with a number of four screws 20 each battery module 12 a significant economic advantage. Because the screws 20 the lower strength class are cheaper than screws of a higher strength class.

Furthermore, the assembly tolerances per compartment or receiving compartment improve 18 , This has a considerable influence on the overall system size, ie on the size of the battery 10 , It can therefore be a particularly compact design of the battery 10 or the battery system.

Another advantage is that the battery modules 12 in the plane perpendicular to the shaft 22 the respective screw 20 , so in the xy plane according to 3 , even under operating loads can no longer translate. The xy plane according to 3 can in the motor vehicle, in which the battery 10 is installed, corresponding to the plane defined by the vehicle longitudinal axis x and the vehicle transverse axis y plane.

Due to the reduced displacements of the battery modules 12 in the storage compartments 18 are also the mechanical influences on module connectors 54 particularly reduced, which according to 1 the individual battery modules 12 electrically conductively connect together. In such module connectors 54 it may in particular be high-voltage lines, which between the respective electrical poles of the electrically connected battery modules 12 are arranged. A shift of the module connector 54 and also a force influence on the respective module connector 54 can be significantly reduced depending on the design of this high-voltage cable or this high-voltage connector.

In 3 is from the carrying device 16 only the tab 36 shown. Through a central passage opening, which within the projection 44 is formed, occurs according to 3 the shaft 22 the screw 20 therethrough. By tightening the screw 20 can be the partial area of the blind rivet nut 32 deform, which through the tab 36 passes. This is in the end 34 or end of the blind rivet nut 32 formed an internal thread, which with one on the shaft 22 the screw 20 trained external thread is engaged. The blind rivet nut 32 forms as a result of tightening the screw 20 a radial bead, with the tab 36 then between this bead and the head of the blind rivet nut 32 is arranged. The head of the blind rivet nut 32 in this case comprises the projection 44 and the collar 48 ,

Out 3 It is particularly clear that the blind rivet or blind rivet nut 32 the present example designed as a cone projection 44 on a support surface, which in part through the collar 48 is provided. Part of the support surface is thus still through the collar 48 educated. In the area of the support surface or in the mounting area receive the battery modules 12 the one with the lead 44 corresponding chamfer or indentation 46 , Through the interaction of the cone-shaped projection 44 with the recess 46 is limited in each screw depending on the fit of the degree of freedom in the xy plane. Here, a wedge principle is realized by the projection 44 in the depression 46 is included.

The rotational degree of freedom is preferably restricted by the adaptation of a further attachment point. For this purpose, the module housing 14 in a first of the corner areas 26 the depression 46 have, the internal dimensions according to 3 with external dimensions of the projection 44 correspond. The module housing 14 preferably in a first corner area 26 diagonally opposite corner area 26 as a structural element one in the module housing 14 trained, slot-shaped depression on. The slot-shaped depression extends in the direction of a connecting line from the first corner region 26 to the opposite corner area 26 , In this direction, a length of the recess is greater than the outer dimensions of the projection 44 , Perpendicular to the length, however, the internal dimension of the recess corresponds to the outer dimension of the projection 44

By providing the recess 46 in the respective mounting region of the module housing 14 is the mating system also on the battery module 12 implemented accordingly.

Particularly low costs can be realized if all blind rivet nuts 32 the battery 10 the projections 44 exhibit. Because of such a strategy of using identical parts, cost advantages can be achieved.

Overall, the example shows how can be used by the invention, a modified blind rivet for a positive connection.

Claims (10)

Battery for a motor vehicle, comprising at least one battery module (12) which has a plurality of battery cells, which are arranged in a module housing (14) of the battery module (12), and with a carrying device (16) on which the at least one battery module ( 12), wherein the at least one battery module (12) by means of at least one screw (20) on the support means (16) is fixed, which engages in a nut (32), wherein a structural element (44) of the nut (32) and a structural element (46) of the module housing (14) forming a form fit with each other, wherein the nut is formed as blind rivet nut (32) having a projection (44) as the structural element of the nut, wherein the structural element of the module housing (14) one in the Module housing (14) formed with the projection (44) corresponding recess (46), wherein the projection (44) is received in the recess (46). Battery after Claim 1 , characterized in that the projection (44) is formed as a cone with a central passage opening for the screw (20), wherein a shaft (22) of the screw (20) passes through a fastening eye (28) which on the module housing (14 ) is trained. Battery after Claim 2 , characterized in that the fastening eye (28) has a determinable in the direction of the shaft (22) of the screw (20) length, which more than a quarter of a in the direction of the shaft (22) of the screw (20) determinable height (30) of the module housing (14) is. Battery after Claim 2 or 3 , characterized in that the blind rivet nut (32) has a collar (48) adjoining the cone in the radial direction, the upper side (50) of which rests against a lower side (52) of a fastening region of the module housing (14). Battery according to one of the preceding claims, characterized in that the carrying device (16) comprises a bottom part (42) and at least one side wall (38, 40) of a receiving compartment (18) of a battery housing of the battery (10). Battery after Claim 5 characterized in that a tab (36) through which a free end (34) of the nut (32) passes and which is spaced from the bottom portion (42) is connected to the at least one side wall (38, 40). Battery according to one of the preceding claims, characterized in that the module housing (14) is substantially cuboidal and by means of at least two screws (20) on the support means (16) is fixed, which in corner regions (26) of the module housing (14) are, wherein the respective screw (20) associated nut (32) each having the structural element (44). Battery after Claim 7 , characterized in that the module housing (14) in a first of the corner regions (26) as the structural element of the module housing (14) comprises a recess (46) formed in the module housing (14), the internal dimensions of which correspond to external dimensions of the projection (44) in which the module housing (14) comprises in a further corner area (26) as the structural element of the module housing (14) a slot-shaped recess (46) formed in the module housing (14) which projects in the direction of a connecting line from the first corner area (26 ) extends to the further corner region (26). Battery according to one of the preceding claims, characterized in that the battery (10) is designed as a high-voltage battery, which has a plurality of the support means (16) fixed battery modules (12). Motor vehicle with at least one battery (10) according to any one of the preceding claims, wherein by means of the battery (10) electrical energy for a trained for advancing the motor vehicle drive unit of the motor vehicle is provided.

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